US3800109A

US3800109A - Manual control for gas and electric controlled apparatus

Info

Publication number: US3800109A
Application number: US00272639A
Authority: US
Inventors: Gowan E Mc
Original assignee: United Gas Industries Ltd
Current assignee: United Gas Industries Ltd
Priority date: 1971-07-24
Filing date: 1972-07-17
Publication date: 1974-03-26
Anticipated expiration: 1991-03-26
Also published as: GB1393250A

Abstract

A control for selecting the power source for a refrigerator capable of being powered from gas or one of two different electrical supplies has electrical switches mounted adjacent a gas manifold containing a gas cock. A common tool engages both the switches and the gas cock to effect either turning the gas cock on and both the switches off or one of the switches on and the gas cock off.

Description

0 United States Patent [1 1 [111 3,800,109 McGowan Mar. 26, 1974 MANUAL CONTROL FOR GAS AND 3,310,642 3/1967 Zeller 200/6 B x ELECTRIC CONTROLLED APPARATUS 3,299,225 1/1967 Heath 200/6 B 3,213,628 9/1966 Puttfarcken ZOO/61.86 X [75] Inventor: Eri McGowan, pp 3,637,962 1/1972 Fiddler et al. 200/6l.86

England [73] Assignee: United Gas Industries Limited, Primary Examiner james R Scott London England Attorney, Agent, or Firm-Larson, Taylor and Hinds [22] Filed: July 17, 1972 [21] App]. No.2 272,639

[57] ABSTRACT [30] Foreign Application. Priority Data A control for selecting the power source for a refriger- July 24, 1971 Great Bl'ltaln 34826/71 ator capable f being powered f gas or one f two different electrical supplies has electrical switches [52] US. Cl. 200/61.86 mounted adjacent a gas if ld containing a gas [51] Int. Cl. HOlh 9/06 cock A common tool engages both the Switches and [58] held of Search ZOO/6136 6 6 6 BB the gas cock to effect either turning the gas cock on and both the switches off or one of the switches on [56] References Cited and the gas cock ff UNITED STATES PATENTS 3,502,835 3/1970 Batcheller 200/61.86 X 5 Claims, 7 Drawing Figures v PATENTEDMAR26 m4 3.800.109

SHEET 2 OF 4 11 Fla. 2. Q

9 42 5 fi Q 20 26 I9 16 Q 22 I MANUAL CONTROL FOR GAS AND ELECTRIC CONTROLLED APPARATUS This invention relates to controls for use in refrigerators, and particularly to such controls for use in absorption type refrigerators which may be powered either by electricity or by gas.

The invention provides a control for use in a refrigerator comprising a gas cock for connection in a gas path, an electrical switching device for connection in an electrical supply line and common means for operating the gas cock and the switching device such that when the gas cock is turned on the switching device is turned off and vice versa.

The gas cock and the switching device may be operated by rotation of a common tool which engages both the opening and closing means of the gas cock and a cam operating the switching means.

According to yet another aspect the invention provides an absorption-type refrigerator having alternative electrical and gas-powered heating means, temperature-sensitive refrigerator control means including temperature-sensitive gas valve and electrical switch and a control as set forth above. The electrical heating means may comprise two heaters each adapted for use with a different electrical power supply and the electrical switching device is adapted for selecting one or other of the heaters. The gas cock may be operated by means co-operating with the electrical switching device to prevent more than one heater being powered at the same time.

The temperature-sensitive refrigerator control means may be as described and claimed in my co-pending patent application Ser. No. 266,046 filed 14 Feb. 1972.

An embodiment of the invention is shown in the accompanying drawings, in which:

FIG. 1 is a rear view of part of a refrigerator incorporating a gas/electric selector control assembly,

FIG. 2 is a side view of the refrigerator of FIG. 1,

FIG. 3 is a front view of the control assembly shown in FIG. 1,

FIG. 3A is a sectional view taken along line 3A3A of FIG. 3,

FIG. 4 is an end view of the control assembly of FIG.

FIG. 5 is a rear view of the control assembly shown in FIG. 3, and

FIG. 6 is a circuit diagram of a selector switch part of the control assembly of FIG. 3.

An absorption-type refrigerator as shown in FIGS. 1 and 2 includes a condenser 11 and a heater 13. This heater is adapted to be powered in three mutually exclusive ways. The first comprises gas burners supplied with gas through line 14, the second and third comprise electrical heaters adapted to be powered via leads 15 the second from a 12 volt d.c. supply (eg from a car battery) and the third from a mains supply (e.g. 110v or 240v). The refrigerator may therefore be installed in a caravan or other movable vehicle, powered from bottled gas, mains electricity or a battery depending on which is available, convenient, or allowable.

A gas/electric control assembly shown generally at 16 and in more detail in FIGS. 3 to 6, is provided for selecting the kind of heating power and controlling the selected supply thereafter. The total assembly comprises a temperature-sensitive gas/electric control mechanism 17, a removable gas manifold 20 secured to the control mechanism and a selector switch 19 (omitted from FIGS. 3 to 5).

The temperature-sensitive gas/electric control mechanism 17 may be of the kind shown and claimed in my co-pending patent application Ser. No. 266,046. This has a common thermal assembly 18 having a capillary 14' which leads to the cold compartment of the refrigerator to sense the temperature thereof. According to the temperature sensed, the mechanism 17 opens and closes a gas valve and at the same time opens and closes an electrical switch 38 (FIG. 6) so that, powered by the selected form of heating as described hereinafter, the refrigerator cooling circuit is caused to maintain the sensed temperature in a certain range. The mechanism also includes a gas flame failure device comprising a thermocouple connected via line 22 to detect the presence or absence of a flame in the refrigerator gas burner, and to turn off the gas valve when no flame is present. The flame failure device may be over-riden during the starting procedure by direct or indirect manual pressure on a button 23.

The control mechanism 17 has a gas inlet and a gas outlet shown generally by arrows A and B respectively in FIG. 3, through which gas passes via the said gas valve. The gas manifold 20 is removably secured in a gas tight manner to the body of the control mechanism 17 by screws 25. A main gas inlet 26 at one end of the manifold leads to a gas cock 30 and from there to a filter 28. From the filter 28 the gas path passes through a port aligned with the gas inlet A so as to pass through the gas control mechanism 16 and out through gas outlet B which corresponds to another port in the manifold 20. The gas path in the manifold then includes a pressure test point 27 before being connected with the gas line 14.

The gas cock 30 is of the rotatable plug type and is operated by a rotatable spindle 31 (FIGS. 2 and 4) extending from one side of the manifold. The other end of spindle 31 extends from the other side of the manifold and has mounted for rotation therewith a sector shaped washer 32 having two angularly spaced apart shoulders which co-operate with a stop 33 to limit the arc of movement of the spindle 31 to about 225. In the center position of the arc of movement shown in FIG. 5, the gas cock is open. Rotation in either direction from this center position closes the gas cock.

As seen in FIGS. 1 and 2, the selector switch 19 is mounted adjacent spindle 31 and has a cylindrical opening through which access is obtained to the spindle 31. As shown diagrammatically in FIG. 6, the switch comprises a rotatable cam 36. A first pair of spring contact arms 37 are secured to move together while being electrically insulated from one another. One or both of the arms have projections which, ride on the cam surface and are urged toward the cam surface by the spring pressure of the arms. Each arm of the pair carries a contact co-operating with a fixed contact such that in the position shown both contacts are open. When cam 36 is rotated anticlockwise from the central position as seen in FIG. 6 until the indentation 39 thereon is adjacent the projections on the arms 37, the arms 37 are allowed to move to the right and both contacts are made. This completes a circuit from a mains electricity supply (e.g. volts) through the thermally-controlled electrical switch 38 of the control mechanism 17 and terminals 1 and 2 of the selector switch to the said third heater of the refrigerator. When the thermally controlled switch 38 is in the position calling for further cooling of the refrigerator the said third heater is operative.

On the opposite side of the cam 36 are mounted a similar pair of spring contact arms 40 operating in the same was as contact arms 37, but connecting al2 v9lt supply to the said second heatei fhrough the electric switch 38 and terminals 1 and 3 of the selector switch when the cam 36 is turned clockwise from its central position.

The selection of the first, second or third heaters is performed by the drive tool 42 shown in FIG. 2. This comprises a slotted cylinder which passes through the selector switch 19, through a central bore in cam 36 with the slot engaging a drive spline in the cam bore so that rotation of the tool rotates the cam. The end of the tool which passes right through the switch 19 engages the spindle 31 of the gas cock 30, the same slot drivingly engaging a peg on the spindle. The drive spline on the cam and the peg on the spindle are thereby maintained aligned.

With the cam in the central position shown in FIG. 6, the spindle 31 is also in its central position. It will been seen that in this condition the gas cock is open and both sets of spring arms 37 and 40 are held with their contacts open. Only the gas supply is thereby selected. To select one or other of the electrical supplies the tool 42 is turned either clockwise or anticlockwise to the limit of movement set by the washer 32. This action closes the gas cock. Therefore only one of the three sources of heating power can be selected at any time.

As can be seen from a consideration of FIGS. 1 and 2, all the controls to be operated face the front of the refrigerator. They may therefore be operated directly or indirectly from controls inside or on the front of the refrigerator. Access to the rear of the refrigerator is therefore unnecessary in every day operation. The control assembly is shown mounted at an angle to the horizontal for convenience so that the controls to be operated appear in a horizontal line in or on the refrigerator.

The manifold 20 is preferably mounted on the refrigerator in a semi-permanent manner, so that by removing screws 25 the control mechanism 16 can be removed for servicing, also giving access to the filter 28. A mechanical interlock may be provided to ensure that the control mechanism 16 may only be so removed when the main gas cock is turned off and the gas cock could only be turned on when the assembly is complete again.

I claim:

l. A refrigerator control comprising in combination:

a gas cock having a rotatable operating member,

limit stop means operatively associated with the operating shaft of the gas cock to limit rotation of the shaft within a fixed range,

a cam mounted on the operating member of the gas cock,

two sets of normally open switches having respective movable contact arms bearing against the cam, and

respective input terminals connected to the two sets of switches,

one of said sets of switches being closed by rotation of the operating member and hence also the cam in one direction from a neutral position and the other said set of switches being closed by rotation of the operating member and the cam in the opposite direction from the said neutral position, both switches being open and the gas cock being open in said neutral position, such rotation of the member in either direction from said neutral position closing the gas cock, said gas cock controlling in use of the control a gas supply to a refrigerator and the respective switches controlling alternative electrical supplies to the refrigerator through the input terminals.

2. A refrigerator control as defined in claim 1, including a temperature-sensitive gas control valve having temperature-responsive operating means connected thereto for controlling the gas supply to the refrigerator in response to a temperature in the refrigerator, and a gas manifold having means releasably securing it to the temperature-sensitive control valve, and a main inlet, a main outlet, and respective gas passages interconnecting the main inlet and the gas control valve and the gas control valve and the main outlet; the gas cock being mounted in the manifold in the gas passage between the inlet and the gas control valve.

3. A control as claimed in claim 2, wherein said gas manifold includes a gas filter in one of said gas passages.

4. A refrigerator control as defined in claim 1, including a common removable tool adapted to engage the operating member of the gas cock and rotatable between a neutral position in which said gas cock is open and the electrical switches are open and other positions in which the gas cock is closed and a selected one of the switches is closed.

5. A control as defined in claim 4, wherein said tool comprises a slotted cylinder engageable with the gas cock operating member.

Claims

1. A refrigerator control comprising in combination: a gas cock having a rotatable operating member, limit stop means operatively associated with the operating shaft of the gas cock to limit rotation of the shaft within a fixed range, a cam mounted on the operating member of the gas cock, two sets of normally open switches having respective movable contact arms bearing against the cam, and respective input terminals connected to the two sets of switches, one of said sets of switches being closed by rotation of the operating member and hence also the cam in one direction from a neutral position and the other said set of switches being closed by rotation of the operating member and the cam in the opposite direction from the said neutral position, both switches being open and the gas cock being open in said neutral position, such rotation of the member in either direction from said neutral position closing the gas cock, said gas cock controlling in use of the control a gas supply to a refrigerator and the respective switches controlling alternative electrical supplies to the refrigerator through the input terminals.